Apparatus and method for coating pipe surfaces



May 15, 1962 E. GRAY ETAL 3,034,729

APPARATUS AND METHOD FOR COATING PIPE SURFACES Filed April 9, 1958 4Sheets-Sheet 1 IN VENTORS ARTHUR E .GRAY GRAHAM N. G-LEYSTEEN 2W 7AM May15, 1962 Filed April 9, 1958 4 Sheets-Sheet 2 as 44 s 90 90 92 5o 40 Z 464 \//V////I l INVENT OR 5 ARTHUR E. GRAY GRAHAM N. GLEYSTEEN May 15,1962 E. GRAY ETAL APPARATUS AND METHOD FOR COATING PIPE SURFACES 4Sheets-Sheet 3 Filed April 9, 1958 INVENTORS ARTHUR E. GRAY GRAHAM N.GLEYSTEEN fiwl wf-ww ATTORNEYS May 15, 1962 E. GRAY ETAL 3,034,729

APPARATUS AND METHOD FOR COATING PIPE SURFACES Filed April 9, 1958 4Sheets-Sheet 4 INVENTORS ARTHUR E. GRAY GRAHAM N. GLEYSTEEN ATTORNEYSUnited States Patent 3,034,729 APPARATUS AND METHOD FOR CGATING PIPESURFACES Arthur E. Gray and Graham N. Gleysteen, Pittsburgh,

Pa., assignors, by mesne assignments, to Pittsburgh Chemical Company,Pittsburgh, Pa., a corporation of Pennsylvania Filed Apr. 9, 1958, Ser.No. 727,389 6 Claims. (Cl. 239-415) This invention relates to thecoating of pipe interiors and more particularly to an improved apparatusand method for mixing and applying two separate materials, preferably ofthe type which will react with each other, to pipe interiors and thelike.

While the invention is susceptible of general utility, in its morespecific aspects it embodies an apparatus and method for mixing togethertwo materials, one, a bitumen and an epoxy resin mixture and, another, acuring agent for the resin and subsequently distributing the mixedmaterials uniformly to a pipe surface. In dealing with such materials,it is essential to provide an apparatus which will effect a thoroughmixing of the two materials efore the same are applied. Moreover, afterthe materials have been thoroughly mixed, it is also essential that theybe efficiently applied to the pipe surface so as to preclude theformation of voids and other defects in the coating.

The present invention is more particularly concerned with the problem ofapplying or distributing the mixed materials to the pipe surface to becoated. Where the interior of the pipe is to be coated, distribution canbe conveniently accomplished with the use of centrifugal force.Accordingly, the present application discloses apparatus whereby themixed materials are applied to pipe interiors by throwing or moving themixed materials outwardly from a central source through rotation of adistributing member so that it will be evenly deposited by thecentrifugal force of the rotating member onto the interior of the pipe.

While centrifugal force distribution is readily available to be usedwhen coating pipe interiors, it is quite apparent that this action cannot be utilized to coat the exterior surface of the pipe. Thus, anapparatus employing centrifugal force for the application of the mixedmaterial is limited in its utility in that it is completely incapable ofuse in coating pipe exteriors.

Accordingly, it is an object of the present invention to provide anapparatus of the type described which can be easily adapted for use inapplying coatings to either the exterior or interior surface of pipesand the like.

Another object of the present invention is the provision of an apparatusof the type described having an improved mixture distributing nozzlesuitable for application to either the exterior or the interior of apipe or the like.

Still another object of the present invention is the provision of anapparatus of the type described having improved material distributingmeans which is simple in construction, efficient in operation and,economical to manufacture and maintain.

These and other objects of the present invention will become moreapparent during the course of the following detailed description andappended claims.

The invention may best be understood with reference to the accompanyingdrawings wherein illustrative embodiments are shown.

In the drawings:

FIGURE 1 is a somewhat schematic vertical sectional asses/2s PatentedMay 15, 1962 view of an apparatus embodying centrifugal force todistribute the material to a pipe interior or the like;

FIGURE 2 is an enlarged fragmentary side elevational view, partly insection, illustrating the applicator head of the apparatus;

FIGURE 3 is a cross-sectional view taken along the line 33 of FIGURE 2;

FIGURE 4 is a cross-sectional view taken along the line 44 of FIGURE 2;

FIGURE 5 is a fragmentary side elevational view, partly in section,illustrating a modification of the discharge nozzle of the applicatorhead;

FIGURE 6 is a view similar to FIGURE 5 illustrating still anothermodification of the nozzle of the applicator head and a modified form ofthe rotary distributor;

FIGURE 7 is a fragmentary side elevational view of still anothermodified form of the rotary distributor;

FIGURE 8 is a view similar to FIGURE 6 illustrating still anothermodified form of the rotary distributor;

FIGURE 9 is a cross-sectional view taken along the line -9 of FIGURE 8;

FIGURE 10 is a somewhat schematic side elevational view partly brokenaway illustrating an apparatus, embodying the principles of the presentinvention, as used in applying coatings to the exterior surface of apipe or the like;

FIGURE 11 is an enlarged, fragmentary, side elevational view of theapparatus showing the distributing nozzle in section;

FIGURE 12 is a fragmentary front elevational view of the apparatusshowing the distributing nozzle in section;

FIGURE 13 is a bottom view of the apparatus;

FIGURE 14 is a fragmentary, side elevational view of the apparatus,partly in section, showing the same as modified for use in applyingcoatings to the interior surface of a pipe or the like;

FIGURE 15 is a view similar to FIGURE 14 showing a schematic arrangementfor effecting rotary and longitudinal movement of the pipe relative tothe apparatus; and

FIGURE 16 is a cross-sectional view taken along the line 1616 of FIGURE15.

Referring now more particularly to FIGURE 1 of the drawings, there isshown an apparatus, generally indicated at 10, which includes anapplicator head, generally indicated at 12, arranged to apply a coatingof material to the interior of a pipe 14. Means, generally indicated at16, is provided for supporting the pipe 14 in operative positionrelative to the applicator head 12 and for effecting relativelongitudinal movement between the pipe and the applicator head duringthe operation of the latter so that the material distributed by the headwill be received on the pipe as an even coating throughout the interiorthereof. The means 16, schematically illustrated in the drawings,is'operable to elfect a longitudinal movement of the pipe 14 relative tothe stationarily mounted applicator head 12 and it will be understoodthat this arrangement is merely exemplary and that other means may beprovided for this purpose.

In the apparatus illustrated in FIGURE 1, the applicator head 12 isstationarily mounted in cantilever fashion on one end of an elongated,generally U-shaped frame member 18. The other end of the frame member 18is rigidly secured to a suitable base or the like 20. The applicatorhead is arranged to receive two separate materials, one of whichpreferably comprises a bitumen and epoxy resin mixture and the other ofwhich comprises a curing agent for the resin. As shown in FIGURE 1, thebitumen and epoxy resin mixture may be contained in a hopper 22 having apump 24, driven by a suitable motor 26, connected to the discharge endof the hopper and arranged to feed the bitumen and epoxy resin mixtureunder pressure through a conduit 28 to the applicator head 12. Thecuring agent is preferably contained within a hopper 30 having a pump32, driven by suitable motor 34, connected to the discharge end thereofand arranged to deliver the curing agent to the applicator head througha conduit 36. As shown in FIGURE 1, the conduits 28 and 36 may besuitably mounted within the U- shaped frame member 18.

Referring now more particularly to FIGURE 2, the applicator head 12includes a cylindrical body 38 having its rear end counterbored andthreaded, as indicated at 40, so as to threadedly receive a rear endwall 42. The end wall 42 is provided with a pair of longitudinallyextended spaced passageways 44 and 46 arranged to be connected with theends of the conduits 28 and 36 respectively. The opposite end of thecylindrical body 38 of the applicator head is closed by a forward endwall 48. The rear end wall 42 is centrally apertured, as at 50, and theend wall 48 is likewise centrally apertured, as indicated at 52, so asto receive a shaft 54 which extends axially through the applicator head.As best shown in FIGURE 1, the shaft 54 extends rearwardly within theU-shaped frame member 18 and its rearward end is journaled by anysuitable means, such as bearing blocks 56, and connected with a motor 58to be driven thereby.

The forward end of the shaft extends into and is journaled within theapplicator head by any suitable means. As shown in FIGURE 2, the endwalls 42 and 48 are preferably recessed to receive ball bearingassemblies 60 and 6 2 respectively, to accomplish this purpose, whichengage and serve to journal the shaft 54 within the applicator headalthough, it will be understood that other journal means, such as sleevebearings or the like, may be employed, if desired.

The interior of the cylindrical body 38 between the end walls 42 and 48defines an elongated cylindrical mixing chamber 64 within which thematerials introduced therein through the passageways 44 and 46 areintimately intermixed. To effect this mixing of the two materials, thepassageway 44 for the bitumen and epoxy resin mixture has a short tube66 connected therewith which is arranged to direct the material passingthrough the passageway 44 into the mixing chamber 64 in an area adjacentthe shaft 54 or axially within the mixing chamber. The outlet of thepassageway 46 has a deflector block 68 connected therewith which isarranged to direct the curing agent issuing therefrom outwardly towardthe periphery of the mixing chamber.

Mounted on the shaft 54 within the mixing chamber 64 adjacent the rearend wall 42 is a rear mixing blade assembly 70, which preferably maycomprise a disk of metal having blades struck therefrom and bent so asto impart not only a rotary motion to the materials within the mixingchamber, but a forward longitudinal motion as well. The blade assembly70 is secured to the shaft by any suitable means, such as a rigidcentral hub 72 having a set screw 74 threaded therein for engagementwith the shaft. Mounted in spaced relation on the shaft 54 forward ofthe rear mixing blade assembly 70 is an intermediate mixing bladeassembly 76 of substantially similar construction and including a rigidhub 78 having a set screw 80 threaded therein for securing the bladeassembly to the shaft. The blade assembly 76 preferably has bladesstruck from a disk of metal and bent in an opposite direction from thoseof the blade assemblies 70 so that in operation, the material is givennot only a rotary motion, but a rearward longitudinal motion as well.Disposed within the mixing chamber 64 adjacent the forward end wall 48thereof is a forward blade assembly 82, which preferably is identicalwith the blade assembly 70 and includes a rigid hub 84 having a setscrew 86 threaded therein for engaging the shaft 54. Like the rear bladeassembly 70, the forward blade assembly 82 is arranged to impart arotary motion and a forward longitudinal motion to the material withinthe mixing chamber. To further aid in agitating the materials within themixing chamber 64, there is provided a plurality of circumferentiallyspaced, longitudinally extending baflles 88 suitably secured to thecylindrical body by any suitable means, such as set screw 90 or thelike.

In order to discharge the material from the mixing chamber, the forwardend wall 48 is provided with a plurality of circumferentially spaceddischarge orifices or apertures 92 through which the material dischargesinto a nozzle 94. The nozzle 94 includes a frusto-conical intermediateportion 96 having a longitudinally extending cylindrical flange 98extending from the rear end thereof, which is interiorly threaded toengage exterior threads formed on the forward end of the cylindricalbody 33. Extending from the forward end of the frustro-conical portion96 is a cylindrical portion llfitl'having an outwardly extending radialflange 102 formed on the forward end thereof.

The shaft 54 extends through the mixing chamber 64 and outwardly throughthe cylindrical portion of the nozzle 94 and and has its outer endarranged to receive a rotary distributor 104. The rotary distributor1114 includes a hollow cylindrical member 106 having the forward endthereof provided with a centrally apertured end wall 1% arranged toreceive the outwardly extending end of the shaft 54 and to be rigidlysecured thereto by any suitable means, such as a nut 110 threaded on theend of the shaft. The opposite end of the cylindrical member 106 extendsover the cylindrical portion 100 of the nozzle and has an inwardlydirected radial flange 112 formed thereon which is disposed in spacedrelation to the nozzle. Extending through the hollow cylindrical member106 is a plurality of circumferentially spaced narrow apertures 114. Asbest shown in FIGURES 2 and 5, for a two inch diameter cylindricalmember 106 the apertures are preferably arranged in six rows around thecircumference of the member 106 and each row preferably containsapproximately 15 apertures. It will be understood that the number ofrows provided will increase with an increase in the diameter of themember 106.

Referring now more particularly to FIGURE 5 in the drawings, there isshown a slight modification of the nozzle 94 in which a separatecylindrical nozzle outlet portion 116 is provided. The inner end of thecylindrical outlet portion 116 may be suitably threaded, as at 1 18, toengage cooperating threads formed in the frusto-conical portion of thenozzle 94. The cylindrical outlet portion 116 includes an outwardlyextending radial flange 120 which is disposed near the rear end of therotary distributor 104.

in FIGURE 6, there is shown a modified nozzle 122 which includes afrusto-conical portion 124 terminating in an outlet 126. A modifiedrotary distributor 128 is secured to the shaft 54 extending outwardlythrough the outlet 126 and includes a hollow cylindrical member 130having a centrally apertured forward end wall 132 arranged to receivethe end of the shaft 54 and to be fixedly secured thereto by anysuitable means, such as a nut 134. The cylindrical member is open at itsopposite end and has a series of circumferentially spaced longitudinallyextending elongated slots 136 formed therein through which the materialis discharged by centrifugal force.

FIGURE 7 illustrates a further modified form of a rotary distributor 138which is similar to the distributor 104 but includes a series ofcircumferentially spaced apertures 140 arranged in spaced spiral rowsabout the circumference of the hollow cylindrical member.

FIGURES 8 and 9 illustrates a further modified form of distributor 142,which comprises a concavo-convex disk 144 having a central apertureformed therein for receiving the end of the shaft 54 and to be fixedlysecured thereto, as by a nut 146. The disk 144 has its concave surfacefacing the discharge outlet of the nozzle and is arranged to receive thematerial issuing therefrom and to distribute the same into the interiorof the pipe by centrifugal force.

In order to facilitate relative longitudinal movement between the pipe14 and the applicator head 12, the latter is provided with a ring 148which is arranged to engage the exterior surface of the cylindrical body38 and to be fixed thereto, as by a set screw 150, in differentpositions of adjustment. Extending outwardly from the ring 148 are aseries of circumferentially spaced guide fins 152 arranged to engage theinterior surface of the pipe 14 and to maintain the applicator head inconcentric relation therewith. As shown in FIGURE 3, three guide fins152 are provided and it will be understood that more or less than threemay be utilized, if desired.

The means 16 illustrated in FIGURE 1 for effecting relative movementbetween the pipe 14 and applicator head includes a U-shaped saddle orguide member 154 which is arranged to receive the pipe and to supportthe same for longitudinal movement. The saddle 154 includes a centralelongated slot 156 with in which a cable 158 may extend. The cable 158has a hook 169 on one end thereof for engaging one end of the pipe andthe opposite end thereof is trained about a pulley 162 and a winch 164powered by a suitable motor 166 or the like.

In the operation of the apparatus illustrated in FIGURE 1, the pipe tobe lined is moved within the saddle 154 over the applicator head 12 withthe hook 16 1 connected with the rear end thereof and the cable 158extended from the winch 164 and then motors 26, 34, 58 and 166 arestarted to commence operation. It will be noted that pumps 24 and 3 2driven by the motors 26 and 34 respectively are operable to introducethe bitumen and epoxy resin mixture from the hopper 22 and the curingagent from. the hopper 30* through the conduits 28 and 36 respectivelyinto the mixing chamber 64 under pressure. The bitumen and epoxy resinmixture is somewhat heavier than the curing agent and, hence, directedaxially into the chamber by means of the tube 66. The curing is directedto the periphery of the mixing chamber by the deflector block 68. Thus,the supply of the heavier material is toward the center of the chamber,while the supply of the lighter material is around the peripherythereof. The blades of the blade assemblies 70, 76 and 82 set thematerial within the mixing chamber into rotary motion and such rotarymotion effects an intermixing of the two materials as a result ofcentrifugal force. That is,

.since the heavier material tends tomove toward the periphery as aresult of the centrifugal action, it will become intermixed with thelighter material supplied therein. In addition to the rotary motionimparted by the blade assemblies, it will be noted that the rear bladeassembly serves to impart a forward longitudinal movement to thematerial within the mixing chamber as Well. The intermediate bladeassembly 76 has the opposite effect and serves to move the two materialsin a rearward longitudinal direction so that there is additionalagitation and mixture due to this arrangement. Finally, the for- Wardblade assembly 82 is arranged to impart a forward longitudinal movementto the material, which is opposed to the longitudinal movement of theintermediate blade so that still more agitation and intermixing of thematerials is obtained in this manner. As noted above, all three of theblade assemblies serve to impart a rotary movement to the materialwithin the mixing chamber and the provision of the baffles 88 serves toagitate the materials in rotary motion so that they are not separated asa result of centrifugal action, but are continuously agitated. Finally,the movement of the materials outwardly through the restricted orifices92 achieves a still further intermixing as a result of the bafflingeifect of portion of the walls defining the orifices. The total effectof these four distinct intermixing actions, that is, (1) the movement ofthe heavier material into the lighter material as a result ofcentrifugal action, (2) the agitation caused by the longitudinalmovements imparted in ops posite directions by the blade assemblies, (3)the agitation of the-rotating mass caused by the baffles 88 and (4) theagitation of the mass caused by its passage through the orifices 92,serves to intimately intermix the two materials supplied within themixing chamber.

Since the materials are supplied within the mixing chamber 64 underpressure by the operation of the pumps 24 and 32, they will bedischarged therefrom under such pressure, after being thoroughly mixed,as indicated above, through the outlet apertures 92 within the forwardend wall 48. The mixed materials then enter within the frustro-conicalportion of the nozzle and issue outwardly into the rotary distributor1114 through the cylindrical nozzle portion around the shaft 54. Thematerial within the rotary distributor 104 discharges through theapertures 114 and the hollow cylindrical member 106 due to thecentrifugal force created as a result of the rotary motion of thedistributor.

In this manner, the two materials are first intimately intermixed andthe-n subsequently distributed to the interior of the pipe 14. It willbe understood that the pipe 14 is moved at a uniform rate of speedduring the operation of the applicator head so that a coating of uniformthickness is applied to the interior thereof as the mixed materialsdischarge through the apertures in the distributor 104. The arrangementof apertures illustrated in the distributor 164 shownin FIGURES 1-4 ispreferable and the provision of the flange 112 serves to preventspillage or leakage of the material axially outwardly from the hollowcylindrical member 106. The distributor 128 illustrated in FIGURE 6achieves satisfactory results and does not require the utilization ofthe inwardly directed flange. The distributor 138 of FIGURE 7 operatesquite similar to the distributor 104 and is preferable for someapplications. The concavo-convex disk 144 of FIGURE 8 is particularlyadvantageous due to its sim plicity of construction. This distributormerely receives the material isssuing from the nozzle outlet and movesthe same outwardly by centrifugal action.

In general, the mixed materials must have sufficient viscosity to adhereto the pipe interior without running. However, the less viscous themixed materials are, the more readily they can be handled to completelycover the pipe interior uniformly throughout. It is also desirable tooperate the applicator head at a medium to high rpm. Furthermore, it ispreferable to operate the pump at a relatively low rate and with a lowspeed movement between the applicator head and pipe so as to apply arelatively thick coating to the interior of the pipe of the order of 15mils or more. With such an application, an uninterrupted coating ofuniform thickness is applied to the pipe.

In order to reduce the viscosity of the epoxy resinbitumen composition,there can be added a solvent, or thinner, such as an aromatichydrocarbon, or mixtures of aromatic hydrocarbons, e.-g., toluene,xylene, or solvent naphthas, for example. The epoxy ethers or resinssuitable for use in the compositions of the invention contain along withethereal oxygen, glycidyl groups in such quantity that the material hasa 1,2-epoxy equivalency in the average molecule of greater than one. Bythe epoxy equivalency, reference is made to the average number of1,2-epoxy groups contained in the average molecule of the ether.

A preferred group of epoxy ethers for use in the invention is preparedby reacting a dihydric phenol with epichlorhydrin in alkaline solution.These products are of resinous character and in general are solidmaterials at normal temperature (20-30 0.). Any of the various dihydricphenols are used in preparing these glycidyl '7 ethers, includingmononuclear phenols like resorcinal, catechol, hydroquinone, etc., onpolynuclear phenols like his (4-hydroxyphenyl -2,2-propane bis-phenol)4,4'-dihydroxy benzophenone, bis-(4-hydroxyphenyl) -1,1-ethane,

bis- 4-hydroxyphenyl) 1,1-isobutane,

bis- 4-hydroxyphenyl) -2,2-butane,

bis- (4-hydroxy-2-methylphenyl) -2,2-propane, bis-(hydroxy-Z-tertiarybutyl phenyl)-2,2-propane, bis- 2-dihydroxynaphthyl) -methane,

1,5-dihydroxy napthalene, etc.

The product may be represented by the formula:

wherein n is an integer, preferably from 1 to 7, and R represents thedivalent hydrocarbon radical of the dihydric phenol. The preferred epoxyethers for use in the invention are those having epoxy values no lessthan 0.20 (pyridinium chloride method), and melting points no greaterthan 80 C. (Durrans mercury method). The preferred phenol is bis-phenolA.

Less preferably, there can be used 1,2-epoxy-containing polyethers ofpolyhydric alcohols, such as polyglycidyl ethers thereof, like thediglycidyl ether of ethylene glycol, propylene glycol, trimethyleneglycol, diethylene glycol, triethylene glycol, glycerol, dipropyleneglycol and the like. Other typical ethers of this class include glycidylethers of polyhydric alcohols having a 1,2-epoxy equivalency greaterthan one, such as the polyglycidyl ethers of glycol, diglycerol,erythritol, pentaglycerol, mannitol, sorbitol polyallyl alcohol,polyvinyl alcohol, and the like.

In general, the glycidyl ether resin will have an epoxy equivalencygreater than 1 and usually less than 2. The epoxy equivalency may bedefined as the number of epoxy groups per molecule in contrast to theepoxy value which is the number of epoxy groups in 100 grams of theresin.

While the epoxy resin can be utilized by itself, it has been foundpreferable to employ a mixture of the epoxy resin and a bituminousmaterial, such as coal tar pitch. The pitch can be present, if desired,as coal tar or a liquid organic vehicle, such as aromatic high flashnaphtha creosote oil, ketones, chlorinated solvents, toluene or xylene,can be added to the pitch. Generally, to 90 parts of epoxy resin and 90to 10 parts of pitch based on 100 parts by weight of the total epoxyresin-pitch content are employed. In addition to the coal tar pitch andepoxy resin, there can also be added finely divided fillers, e.g.,silica, talc, clay, slate, flour, diatomaceous earth, mica, etc., aswell as solvents, as set forth previously. The epoxy resin-bituminouscomposition is introduced through conduit 28 to the applicator head 12.

The curing agent can be a polyfunctional amine, such as ethylenediamine, diethylene triarnine, benzyl dimethylamine, ethylene triamine,3 dimethylaminopropylamine, 3-diethylaminopropylamine, tetraethylenepentamine, triethylene tetramine and the like. Additional curing agentsinclude N-hydroxyethyl diethylenetriamine, tri-(dimethylaminomethyl)phenol, m-phenylene diamine, dicyandiamide, melamine, piper-azine,diacetone diamine, 4,4'-diaminodiphenyl sulfone, sodium hydroxide,potassium hydroxide, sodium phenoxide, acid materials preferably havinga plurality of acid groups, e.g., oxalic acid, phthalic anhydride,citric acid, tricarbyllic acid, aconitic acid, itaconic acid, malicacid, diglycollic acid, phosphoric acid, n-butyl dihydrogen phosphate,diethyl ortho phosphate, hexaethyl tetraphosphate, Friedel-Crafts metalhalides, e.g.,. aluminum chloride, zinc chloride, ferric chloride, borontrifiuoride, boron-fluoride-diethyl ether complex, boron-fluoride-phenolcomplex, diisocyanates, (e.g., 2,4- toluene diisocyanate) andpolyamides, e.g., long chain fatty acid amides, such as Versamid 115 andVersamid 125. The curing agent is introduced through conduit 36 to theapplicator head 12.

The curing agents may be used in various amounts, although they areusually employed in the range of from 0.05 to 0.25 part per part byweight of epoxy resin. While the bituminous material is normally addedtogether with the epoxy resin through conduit 28, it is possible to addthe bituminous material with the curing agent through conduit 36. Theresin and curing agent, however, should always be added through separatelines to the applicator head.

While, as previously stated, the ratio of epoxy resin to bituminousmaterial, e.g., coal or tar pitch, can be widely varied, usually from 15to 50 parts of resin and from to 50 parts of pitch based on parts ofepoxy resin-pitch content are employed.

Frequently, it is desirable to add a minor amount of chlorinated rubber(Parlon) or rubber hydrochloride to the composition. Generally, thechlorinated rubber or rubber hydrochloride is used in an amount of 0.1to 5% of the total composition by weight.

Thixotropic agents, e.g., labosil (a collodial silica formed in a hightemperature vapor phase flame hydrolysis process which produces anextremely fine product with a particle diameter of about 15millimicrons; chemically it is practically a pure silica with an averageSIO content of 919 to 99.7%) and'quaternary ammonium clays, e.g. Bentone34 (dimethyl dioctadecyl ammonium bentonite) can also be added in anamount of 1 to 5% of the total composition.

Unless otherwise stated, all parts are by weight. In a specific exampleusing the apparatus of FIGURE 2, through conduit 28 there was pumpedcomponent A, a

r mixture of 30 parts of an epoxy ether resin from bisphenol A andepichlorhydrin (melting point 9 C. and epoxy value 0.50), 0.6 partParlon, 29.4 parts of coal tar pitch, 20.0 parts of aromatic high flashnaphtha, 9 parts mica, 10 parts of talc and 1 part of cabosil.Simultaneously, through conduit 36, there were pumped component B, amixture of 5 parts of diethylene triamine dissolved in 5 parts of mixedxylenes. Thus, the material was pumped through conduit 28 in an amount10 times as much as that pumped through conduit 36. The drive shaft 54was rotated at a speed of 4350 rpm. Utilizing these conditions,blemish-free coverage of a 3 diameter pipe was obtained by moving thepipe at a rate to obtain an 18 mils coverage.

In another example where component A was diluted with 12.5% by volume ofxylene but the ratio of feed of component A to component B wasmaintained at 10 to 1, blemish-free coverage of the 3 diameter pipe wasobtained when the shaft was rotated at a speed of 2333 rpm. and the pipewas moved at a rate to give a coverage of 16 mils thickness.

The above description is disclosed in copending application Serial677,468, filed August 12, 1957 by Arthur G. Gray. The present inventionis more particularly concerned with certain improvements in theapplicator head 12 which render the same applicable to coat the exteriorsurfaces of pipes as well as the interior surfaces thereof.

Referring now more particularly to FIGURES 10-13, there is shown anapplicator head 200 embodying the principles of the present invention.In general, the head is the same as the head 12 previously describedexcept that the nozzle 94 and rotary distributor 104 are replaced by anadapter member 202 and a nozzle 204 of improved construction. Thus, theapplicator head 200 includes the mixing chamber 64 wherein the materialsare separately supplied under pressure to be intimately intermixed bythe four actions previously noted.

The mixed material issuing through the orifices 92 is received in theadapter member 202 which preferably includes a large interiorly threadedend 206 arranged to equal to the total interior cross-sectional area ofthe orifices 92. The opposite end of the coupling 210 is rigidlysecured, as by welding or the like, to the central portion of a pipesection 212 of similar size. The pipe section 212 is formed with a smallbut even bend, along a circular arc of large radius. The curvature ofthe bend is such that when cut longitudinally in half along a planesurface perdpendicular to the plane of the curve of the arc, theinterior cross-section of the pipe at either end is about one-half ofthe interior cross-section at its midpoint. The cut side of the pipesection 212 is machined and fitted with a flat machined plate 214, thelatter being secured in a position disposed in a plane perpendicular tothe axis of the coupling 210, by any suitable means, such as screws 216or the like.

The open ends of the pipe section 212 are closed by rigidly securingtherein as by welding or the like, two end disks 218 of generallysemi-circular configuration. The material in the nozzle is arrangedto bedischarged through a desired number of evenly staggered slits 220 formedin the plate 214 between the ends thereof. As best shown in FIGURE 13,three such slits are provided although, it will be understood that thisnumber may be increased, if desired.

FIGURE 10 illustrates one arrangement for utilizing the applicator head2% to apply a coating of the type previously described to the exteriorsurface of a pipe 222. It will be understood that the essentialcondition of the arrangement is to effect a relative longitudinal androtary movement between the pipe and applicator head and that thiscondition can be satisfied by various structural arrangements. In thearrangement shown, the head 2% is mounted in a fixed position and thepipe is moved past the head with a rotary and longitudinal movement toeffect the essential relative movement. It is possible to rotate thepipe only While moving the head longitudinally with respect thereto orto hold the pipe stationary and rotate the head together with suchlongitudinal movement.

As shown in FIGURE 10, the pipe is carried by a pipe carrier or frame224 appropriately supported by wheels 226 riding in suitablelongitudinally extending tracks 228 or the like. One end of the pipe issupported on the frame by a chuck 230 or the like arranged to engagewithin the pipe end and having a shaft 232 extending therefrom. Theshaft 232 is suitably connected with a variable speed motor 234 mountedon the adjacent end of the frame.

The opposite end of the pipe is supported from the frame 224 by anysuitable means, such as a flanged disklike element 236 engageable withinthe pipe end and rotatably carried by a bearing member 238 detachablymounted on the adjacent end of the frame 224 in any appropriate manner.

Longitudinal movement of the pipe 222 is accomplished by moving thewheeled frame along the tracks 228 by any suitable means. As shown,there is provided a motor 240 having a cable reel 242 mounted on itsdrive shaft. A cable 244 is wound on the reel 242 and extends upwardlytherefrom around a pulley 246 and then back to the far end of the framewhere it is rigidly secured, as indicated at 248.

In operation, the applicator head 200 is mounted in fixed position andprovided with suitable pumps and motors in a manner similar to thatshown in FIGURE 1. The wheeled frame 224 having a pipe 222 mountedthereon is initially positioned so that the applicator head nozzle 204discharges adjacent one end thereof a desired distance from the exteriorsurface thereof. Actuation of the motors 234 and 240 at predetermineddesired speeds effects both rotary and longitudinal movement of' thepipe relative to the nozzle. By relating the discharge of material fromthe nozzle to the speed of rotational and longitudinal movement of thepipe, an even coating of material of a desired thickness is applied tothe entire exterior surface of the pipe.

In FIGURES 14-16 there is shown an arrangement whereby the applicatorhead 200 can be modified to apply a coating to the interior of a pipe.The nozzle 204- is utilized as in the arrangement disclosed in FIGURES10-13. The adapter member 202 is replaced by an adapter member 250having a large interiorly threaded end 252 arranged to be engaged on theexterior threads formed on the forward end of the cylindrical body 38.As before, the adapter member necks down throughout its extent from theend 252 and terminates in a relatively small, interiorly threadedopening 254. However, the opening is disposed adjacent the periphery ofthe large end 252 rather than being concentric therewith.

Threadedly engaged within the opening 254 of the adapter member is oneend of a short horizontal pipe coupling 256, the other end of which isthreadedly engaged within an elbow 258. A vertical pipe coupling 260 isthreadedly connected with the opposite end of the elbow and extendsdownwardly therefrom. The lower end of the vertical coupling 260 isthreadedly received in the upper end of a sleeve 262, the lower end ofwhich is connected with the threaded end of the coupling 210 of thenozzle. The length of the horizontal and vertical pipe couplings aresuch as to dispose the nozzle slits 220 as close as convenientlypossible to the adapter member and a desired distance away from the pipeinterior to be coated.

Again, in order to utlize the modified applicator head 26% to apply acoating to a pipe interior, an arrangement must be provided to eifectboth rotary and longitudinal movement relatively between the applicatorhead and the pipe. While any suitable construction may be employed, thearrangement shown includes a generally troughshaped pipe carrier 264supported at opposite ends by wheels 266 suitably mounted thereon andarranged to ride on longitudinally extending tracks 268 or the like.

Mounted in the lower portion of the pipe carrier at opposite endsthereof is a pair of pipe rotating and supporting rollers 270. Therollers are driven by any suitable means to impart rotation to a pipe272 received in the carrier. As shown such means includes a variablespeed motor 274 mounted on one end of the carrier and having alongitudinally extending shaft 27 6 drivingly connected therewith,driving rollers 278 being fixed to the shaft 276 in rolling contact withthe rollers 270. In order to stabilize the pipe Within the carrier,idler rollers 280 are journaled in opposite sides of the pipe carrieradjacent each roller 270.

Longitudinal movement of the carrier is efiected by means of a motor(not shown) similar to the motors 166 and 240 previously described, suchmotor being arranged to reel in a cable 282 fixed, as at 284, to thepipe carrier.

The modified applicator head is fixedly mounted in a manner similar tothat shown in FIGURE 1. Since both rotary and longitudinal movement areinvolved, the fins 152 previously described are replaced by ballbearings 286. As shown there are four ball bearings provided incircumferentially spaced relation about the exterior of the cylindricalbody 38, each ball bearing 288 being mounted within a housing rigidlysecured as by welding or the like to the body 3-8.

The operation of the arrangement shown in FIGURES 14-16 is similar tothat previously described in connection with the arrangement of FIGURES10-13 so that a detailed description thereof is not believed to benecessary. Briefly, the pipe 272 is moved to the right, as viewed inFIGURE 14, while motor 274 is actuated to rotate the same through shaft276 and rollers 270 and 278. By relating the discharge of materialthrough the nozzle slits with the speed of rotative and longitudinalpipe travel, an even coating of a desired thickness is applied to theinterior surface of the pipe.

It will thus be seen that the objects of this invention have been fullyand effectively accomplished. It will be realized, however, that theforegoing specific embodiment has been shown and described only for thepurpose of illustrating the principles of this invention and is subjectto extensive change without departure from such principles. Therefore,this invention includes all modifications encompassed within the spiritand scope of the following claims.

We claim:

1. In an apparatus of the type described, the combination comprising anapplicator head defining an elongated mixing chamber, meanscommunicating with one end of said chamber for directing separatematerials under pressure therein, rotary shaft means extendinglongitudinally within said mixing chamber, blade means carried by saidshaft means for mixing the separate materials entering said mixingchamber, the opposite end of said chamber having orifice means thereinthrough which the mixed materials are discharged from the mixingchamber, an adapter member fixed to said applicator head exterior ofsaid chamber to receive the mixed material discharging therefrom, saidmember having a reduced end extending from said chamber and a nozzlefixedly carried by said member in communication with the reduced endthereof for receiving at one end the material from the reduced end ofsaid member and discharging the same directly onto a pipe surface,whereby both the interior and exterior of a pipe may be coated by thematerial ejected from said nozzle.

2. The combination as defined in claim 1 wherein said nozzle comprisesan elongated pipe section having a pipe coupling rigidly secured to oneside thereof intermediate its ends in communication \m'th the hollowinterior thereof, said section having its opposite side terminatinglongitudinally along a plane perpendicular to the axis of said pipecoupling, said pipe section being extended longitudinally in the planeof said pipe coupling axis so that the interior cross-sectional areaadjacent said coupling is approximately twice the interior cross-sectional area adjacent its ends, means closing the ends of said pipesection and a flat plate fixed to the longitudinally terminating side ofsaid pipe section and having discharge openings therein.

3. The combination as defined in claim 2 wherein said discharge openingcomprises a plurality of staggered longitudinally extending slits.

4. In an apparatus of the type described, a nozzle comprising anelongated pipe section extending longitudinally into an arcuateconfiguration and having a central inlet opening in the convex side ofits curvature, said section terminating longitudinally along its concaveside in a plane perpendicular to a plane passing through the axis ofsaid pipe section so that the interior cross-sectional area adjacentsaid inlet opening is approximately twice the cross-sectional areaadjacent its ends, means closing the ends of said pipe section, and aplate fixed to the longitudinally terminating side of said pipe sectionand having discharge openings formed therein.

5. A nozzle as defined in claim 4 wherein said discharge openingscomprise transversely staggered longitudinally extending slits.

6. In an apparatus of the type described, the combination comprising anapplicator head defining an elongated cylindrical mixing chamber forreceiving separate materials one of which is heavier than the other,means adjacent one end of said chamber for directing the heaviermaterial into said chamber adjacent its axis, means adjacent said onechamber end for directing the other material into said chamber adjacentits periphery, an axial shaft rotatable within said chamber, spacedblade means on said shaft operable to impart a rotary motion to thematerials within said chamber so as to cause an intermixing of thematerials as a result of the centrifugal action of the heavier materialwith respect to the other material and to impart axial movements to thematerials in opposite directions so as to effect further intermixing,longitudinally extending baffie means on the interior periphery of saidmixing chamber operable to impart turbulence to the materials withinsaid chamber passing thereby with a rotary motion so as to effect stillfurther intermixing, means adjacent the other end of said chamberthrough which the intermixed materials within said chamber aredischarged, a necked down member fixed in surrounding relation to theother end of said chamber to receive the materials dischargingtherethrough, and a nozzle having its one end fixed to said necked downmember, said nozzle having discharge openings at its other end fordischarging material therethrough to a pipe surface.

References Cited in the file of this patent UNITED STATES PATENTS1,013,364 Behm Jan. 2, 1912 1,039,383 Goughnour Sept. 24, 1912 1,186,226Parker June 6, 1916 1,208,165 Kent Dec. 12, 1916 1,895,890 Meng Jan. 31,1933 2,185,570 Ridley Jan. 2, 1940 2,280,751 Davis Apr. 21, 19422,287,448 Perkins June 23, 1942 2,575,353 MacEvoy Nov. 20, 19512,578,667 Brennan Dec. 18, 1951 2,814,827 Snow et a1. Dec. 3, 19572,839,026 Matheny June 17, 1958

